Haversine formula for getting the distance between two points given latitudes and longitudes (formats {lat: float, lon: float}).

haversine.py

from math import radians, cos, sin, asin, sqrt


def haversine(alat, alon, blat, blon):
    R = 6371  # Earth's radius in KM
    
    alat, alon, blat, blon = map(radians, [alat, alon, blat, blon])
    clon = blon - alon
    clat = blat - alat
    
    a = (sin(clat / 2)) ** 2 + cos(alat) * cos(blat) * (sin(clon / 2)) ** 2
    c = 2 * asin(sqrt(a))
    
    distance = (R * c)
    
    return distance